remove setting error to undefined to enable SSR with Next.js (getServerSideProps)

Author: gfortaine

src/core/buildSlice.ts

@@ -98,7 +98,7 @@ export function buildSlice({
             if (substate.requestId !== meta.requestId) return;
             substate.status = QueryStatus.fulfilled;
             substate.data = copyWithStructuralSharing(substate.data, payload.result);
-            substate.error = undefined;
+            delete substate.error;
             substate.fulfilledTimeStamp = payload.fulfilledTimeStamp;
           });
         })

test/errorHandling.test.tsx

@@ -148,7 +148,6 @@ describe('query error handling', () => {
         isError: false,
         isSuccess: true,
         data: { value: 'success' },
-        error: undefined,
       })
     );
   });